gem5/src/mem/ruby/structures/DirectoryMemory.cc

/*
 * Copyright (c) 1999-2008 Mark D. Hill and David A. Wood
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions are
 * met: redistributions of source code must retain the above copyright
 * notice, this list of conditions and the following disclaimer;
 * redistributions in binary form must reproduce the above copyright
 * notice, this list of conditions and the following disclaimer in the
 * documentation and/or other materials provided with the distribution;
 * neither the name of the copyright holders nor the names of its
 * contributors may be used to endorse or promote products derived from
 * this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
 * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
 * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
 * A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
 * OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
 * LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */

#include "base/intmath.hh"
#include "debug/RubyCache.hh"
#include "debug/RubyStats.hh"
#include "mem/ruby/slicc_interface/RubySlicc_Util.hh"
#include "mem/ruby/structures/DirectoryMemory.hh"
#include "mem/ruby/system/System.hh"

using namespace std;

int DirectoryMemory::m_num_directories = 0;
int DirectoryMemory::m_num_directories_bits = 0;
int DirectoryMemory::m_numa_high_bit = 0;

DirectoryMemory::DirectoryMemory(const Params *p)
    : SimObject(p)
{
    m_version = p->version;
    m_size_bytes = p->size;
    m_size_bits = floorLog2(m_size_bytes);
    m_num_entries = 0;
    m_numa_high_bit = p->numa_high_bit;
}

void
DirectoryMemory::init()
{
    m_num_entries = m_size_bytes / RubySystem::getBlockSizeBytes();
    m_entries = new AbstractEntry*[m_num_entries];
    for (int i = 0; i < m_num_entries; i++)
        m_entries[i] = NULL;

    m_num_directories++;
    m_num_directories_bits = ceilLog2(m_num_directories);

    if (m_numa_high_bit == 0) {
        m_numa_high_bit = RubySystem::getMemorySizeBits() - 1;
    }
    assert(m_numa_high_bit != 0);
}

DirectoryMemory::~DirectoryMemory()
{
    // free up all the directory entries
    for (uint64_t i = 0; i < m_num_entries; i++) {
        if (m_entries[i] != NULL) {
            delete m_entries[i];
        }
    }
    delete [] m_entries;
}

uint64_t
DirectoryMemory::mapAddressToDirectoryVersion(Addr address)
{
    if (m_num_directories_bits == 0)
        return 0;

    uint64_t ret = bitSelect(address,
                           m_numa_high_bit - m_num_directories_bits + 1,
                           m_numa_high_bit);
    return ret;
}

bool
DirectoryMemory::isPresent(Addr address)
{
    bool ret = (mapAddressToDirectoryVersion(address) == m_version);
    return ret;
}

uint64_t
DirectoryMemory::mapAddressToLocalIdx(Addr address)
{
    uint64_t ret;
    if (m_num_directories_bits > 0) {
        ret = bitRemove(address, m_numa_high_bit - m_num_directories_bits + 1,
                        m_numa_high_bit);
    } else {
        ret = address;
    }

    return ret >> (RubySystem::getBlockSizeBits());
}

AbstractEntry*
DirectoryMemory::lookup(Addr address)
{
    assert(isPresent(address));
    DPRINTF(RubyCache, "Looking up address: %s\n", address);

    uint64_t idx = mapAddressToLocalIdx(address);
    assert(idx < m_num_entries);
    return m_entries[idx];
}

AbstractEntry*
DirectoryMemory::allocate(Addr address, AbstractEntry *entry)
{
    assert(isPresent(address));
    uint64_t idx;
    DPRINTF(RubyCache, "Looking up address: %s\n", address);

    idx = mapAddressToLocalIdx(address);
    assert(idx < m_num_entries);
    entry->changePermission(AccessPermission_Read_Only);
    m_entries[idx] = entry;

    return entry;
}

void
DirectoryMemory::print(ostream& out) const
{
}

void
DirectoryMemory::recordRequestType(DirectoryRequestType requestType) {
    DPRINTF(RubyStats, "Recorded statistic: %s\n",
            DirectoryRequestType_to_string(requestType));
}

DirectoryMemory *
RubyDirectoryMemoryParams::create()
{
    return new DirectoryMemory(this);
}